1. Field of the Invention
The invention relates to an electronic apparatus using a motor, and more specifically relates to an electronic apparatus in which a motor and electronic components such as an LSI controlling a motor are controlled so as not to be overheated.
2. Description of the Related Art
In many of the electronic apparatuses having drive parts, motors are mounted as driving sources for driving the drive parts. Continuous operation of the motor makes the motor itself generate heat by which the motor may have a temperature beyond such a predetermined upper limit that the motor will be broken.
As related art, there has been an electronic apparatus in which a motor temperature is controlled so as not to exceed its upper limit. In the electronic apparatus, a use environment temperature is detected by environment temperature detecting means while a calorific value of a motor is estimated based on power consumption of the motor, and on the basis of the use environment temperature detected by the environment temperature detecting means and the estimated calorific value, the motor is controlled by setting a downtime so that the temperature of the motor does not exceed the predetermined upper limit (for example, refer to Japanese Unexamined Patent Publication JP-A 2005-287253).
However, the related art has a problem that since the downtime is provided to prevent the temperature of the motor from exceeding the predetermined upper limit, it looks to a user as if the operation of the apparatus is temporarily suspended.
Furthermore, owing to recent development of LSI (large scale integration) technique, there exists a device so integrated that a plurality of motors used in the electronic apparatus are all controlled by one LSI chip. For example, the apparatus is created by integrating drivers for driving a carriage motor, a paper feed motor, and moreover, a low current stepper motor for scanner which is used in a facsimile apparatus, etc. It becomes a major issue how heat generation from not only the motors but also such an apparatus can be suppressed to control the apparatus under its upper limit use temperature.